DLRO10HD
10 A Digital Low Resistance Ohmmeter
DLRO10HD
10 Amp Digital Low Resistance Ohmmeter
DESCRIPTION
Augmenting Megger’s DLRO10 and 10X range of low
resistance ohmmeters the DLRO10HD combines ultimate
simplicity of operation with a rugged IP65 case designed for
stable ground and bench operation.
The unit is powered from either its rechargeable battery
or line power making it suitable for continuous testing in
production line/repetitive use environments.
Rotary switch controls are simple and easy to operate in all
weather conditions and with gloved hands. A large, clear,
backlit LCD display is easy to read from a distance.
The DLRO10HD provides significantly enhanced compliance
and is capable of delivering 10 A into measurements up
to 250 mΩ and 1 A into measurements up to 2.5 Ω. The
duration of each test may be up to 60 seconds.
The DLRO10HD is rated CAT III 300 V. A range of test leads
is available to suit the application.
The DLRO10HD provides five test modes each of which is
selected through a simple rotary control.
TEST MODES
Automatic unidirectional mode applies current in one
direction only to speed up the measurement process.
However thermal EMF resulting from dissimilar metal bonds
can cause lower accuracy. Test starts automatically when
probes are connected.
Continuous mode allows repeated measurements to be made
on the same sample. Simply connect the test leads and press
the test button. The measurement is updated every three
seconds until the circuit is broken.
n High or low output power selection for
condition diagnosis
n Rechargeable battery or line power
supply, continuous operation, even with
dead battery
n 10 A for 60 seconds, less time waiting to
cool, great for charging inductance
n High input protection to 600 V, inadvertent
connection to line or UPS voltage will not
blow a fuse
n Heavy duty case: IP65 lid closed, IP54
operational (battery operation only)
n Rotary switch selects one of five test
modes, including auto start on
connection, giving ease of use
Inductive mode is selected when measuring resistance
on, for example, motors and generators. When measuring
inductive loads it is necessary to wait for the voltage to
stabilise as the inductive element is charged. Test leads are
firmly connected to the device under test and the ‘Test’
button pressed. The instrument will pass the selected current
through the sample continuously in one direction only and
take repetitive readings that will gradually decrease to the
true value as the voltage stabilizes. The operator decides
when the result is stable and presses the ‘Test’ button to
terminate the test.
ADDITONAL FEATURES AND BENEFITS
n Rugged case well suited for transportation and includes a
lead set pouch
n Removable lid facilitates easy test lead connection
n Operational ingress protection is IP54 (battery power
only) ensuring protection from the elements
n 7Ah lead acid battery provides extended operation and
can be charged whilst operating from line power
n Rotary mode switch with bidirectional (current reversal
with averaging cancels thermal EMFs), unidirectional,
automatic, continuous and inductive modes
n Large, clear LCD display with backlight and contrast
adjustment
n Auto power off function conserves battery
DLRO10HD
10 A Digital Low Resistance Ohmmeter
The DLRO10HD features two ranges with extended
compliance. Effectively there are two 2.5 Ω and two 250
mΩ ranges one low power, and one high power. The chart
below shows the power output curves for the two 250 mΩ
ranges. Each range provided 10 µΩ resolution allowing the
user to make comparative measurements at either 0.25 Ω or
25 Ω maximum outputs.
ELECTRICAL SPECIFICATIONS
Resistance/Current Ranges
The green resistance ranges on the keypad indicate low
output power (<0.25 W) outputs. Red ranges indicate higher
2.5 W (1 A) and 25 W (10 A) power outputs.
Resolution and Accuracy
Test current accuracy ±10%
Voltmeter input impedance >200 kΩ
Test Resistance Resolution* Basic Full Max.
Current Range Accuracy Scale Power
Voltage Output
0.1 mA 0 to 100 mΩ ±0.2% 25 mV 2.5 µW
2500.0 Ω ±200 mΩ
0.1 mA 0 to 10 mΩ ±0.2% 25 mV 2.5 µW
250.00 Ω ±20 mΩ
1 mA 0 to 1 mΩ ±0.2% 25 mV 25 µW
25.000 Ω ±2 mΩ
10 mA 0 to 100 µΩ ±0.2% 25 mV 250 µW
2500.0 mΩ ±200 µΩ
100 mA 0 to 10 µΩ ±0.2% 25 mV 2.5 mW
250.00 mΩ ±20 µΩ
1 A 0 to 1 µΩ ±0.2% 25 mV 25 mW
25.000 mΩ ±2 µΩ
10 A 0 to 0.1 µΩ ±0.2% 25 mV 0.25 W
2500.0 µΩ ±0.2 µΩ
1 A 0 to 100 µΩ ±0.2% 2.5 V 2.5 W
2500.0 mΩ ±200 µΩ
10 A 0 to 10 µΩ ±0.2% 2.5 V 25 W
250.00 mΩ ±50 µΩ
* The accuracy stated assumes forward and reverse measurements.
Inductive mode or undirectional mode will introduce an undefined error if an
external EMF is present.
Basic accuracy at reference conditions.
SPECIFICATIONS
Temperature Coefficient: < 0.01% per º C, from 5º C to 40º C
Maximum Altitude: 2000m (6562 ft) to full safety
specifications
Display size/type:
Main 5 digit + 2 x 5 digit secondary displays
Battery type: 6 V, 7Ah sealed lead acid
Voltage input range: 90 - 264 V, 50-60 Hz
Charge time: 8 hours
Backlight: LED backlight
Battery life: 1000 Auto (3 sec) tests
Auto power down: 300s
Mode Selection: Rotary switch
Range selection: Rotary switch
Weight: 6.7 kg
Case dimensions: L315mm x W285mm x H181mm
Pouch for test leads: Yes (lid mounted)
APPLICATIONS
The DLRO10HD measures low resistance values in
applications ranging from railways and aircraft to resistance
of components in industry.
Any metallic joint can be measured but users must be aware
of measurement limitations depending on application. For
example, if a cable manufacturer plans to make resistive
measurements on a thin wire, a low test current should be
selected to prevent heating the wire thereby changing its
resistance.
Measurements on electric motors and generators will be
inductive and require the user to understand the inductive
mode and charging process before a correct result is
achieved.
The DLRO10HD is well suited to measuring thick conductors,
bonds and quality of welding because of its 10 A range for
resistance values up to 250 mΩ.
Electromagnetic noise induced into the leads can interfere
with a reading. A noise symbol alerts the user and prevents
a measurement when the instrument detects noise above its
threshold.
When dissimilar metals are joined a thermocouple effect is
created. Users should select a bidirectional mode to ensure
cancellation of this effect. The instrument measures with
current flowing in both directions and averages the result.
Normal mode is initiated by pressing the ‘Test’ button after
connecting the test leads to the unit under test. Continuity of
all four connections is checked. Current is applied in both
forward and reverse direction following which measurement
is displayed.
Automatic mode is started as soon as the probes make
contact. Forward and reverse current measurements are made
and the average value is displayed. This mode is ideal when
working with the supplied DH4 handspikes. Each time the
probes are removed and reconnected to the load a new test
will be performed without the need to press the test button.
DLRO10 DLRO10HD DLRO10X
DLRO10HD
10 A Digital Low Resistance Ohmmeter
Test leads: DH4 lead set included
IP rating: IP65 case closed, IP54 battery operation
Safety rating: In accordance with IEC61010-1, CATIII 300 V
when used with DH7 leads
Operating temperature and humidity
-10° C to +50° C (14° F to 122° F) <90% RH
Reference conditions: 20° C ±3° C
Storage temperature and humidity
-25° C to +60° C, <90% RH
EMC
In accordance with IEC61326-1 (Heavy industrial)
Noise rejection
Less than 1% ±20 digits additional error with 100 mV peak
50/60 Hz. on the potential leads. Warning will show if hum
or noise exceeds this level.
Maximum lead resistance
100 mΩ total for 10 A operation irrespective of battery
condition.
Feature DLRO10 DLRO10HD DLR010X Benefit/s
Power limited ouput Negligible heating, little need for contact
test ranges (<0.25 W) n n n temperature compensation
Can help to highlight contamination
Extends battery life
High power output Can help to highlight weakness with heating, such
test ranges (25 W) n as poor connection due to rough surfaces or
broken strands on cables
Improved inductive load performance
Auto current reversal n n n Cancels out thermal EMFs
Auto start
(continuity detection) n n n Fast operation without pressing test button
Inadvertent connection to live line supply or
High input protection <600 V n n n UPS voltage will not even blow a fuse
Testing just continues as normal
Noise immunity specified at Make measurement in harsh environments
100 mV n n n
Noise limit exceeded indicator n n n Confidence that measurements are not effected
User interchangeable detachable Continuous testing with optional second battery.
battery pack n n Use one battery while second charges
Hang from neck operation n n Ideal for use up ladders and platforms improved
manoeuvrability
Operate from mains/line supply n Continuous testing from mains ideal for
manufacturing applications
Always ready to test no waiting for battery to
charge
IP65 lid closed n Can be transported in any wet conditions
IP54 in use n Can be operated in the rain
Ultra tough case n Built to take the knocks in the most arduous of
conditions
Test result storage with memos Ideal for predictive maintenance systems
n Less errors in writing down test results
Printer and PC output n Save results to your PC or send to a printer
User selectable test limits n Aids rapid testing to specified limits
Feature DLRO10 DLRO10HD DLR010X Benefit/s
Can help to highlight contamination
Extends battery life
High power output Can help to highlight weakness with heating, such
test ranges (25 W)
broken strands on cables
Improved inductive load performance
Auto start
Inadvertent connection to live line supply or
Testing just continues as normal
Noise immunity specified at Make measurement in harsh environments
User interchangeable detachable Continuous testing with optional second battery.
manoeuvrability
Operate from mains/line supply
manufacturing applications
Always ready to test no waiting for battery to
charge
IP65 lid closed
IP54 in use
Ultra tough case
conditions
Test result storage with memos Ideal for predictive maintenance systems
Printer and PC output
User selectable test limits
Feature DLRO10 DLRO10HD DLR010X Benefit/s
n n nn n n
Can help to highlight contamination
Extends battery life
High power output Can help to highlight weakness with heating, such
broken strands on cables
Improved inductive load performance
n n nn n n
Auto start
n n nn n n
Inadvertent connection to live line supply or
n n nn n n
Testing just continues as normal
Noise immunity specified at Make measurement in harsh environments
n n nn n n
n n nn n n
User interchangeable detachable Continuous testing with optional second battery.
n nn n
manoeuvrability
manufacturing applications
Always ready to test no waiting for battery to
charge
conditions
Test result storage with memos Ideal for predictive maintenance systems
Printer and PC output
User selectable test limits
Feature DLRO10 DLRO10HD DLR010X Benefit/s
n n nn n n
Can help to highlight contamination
Extends battery life
High power output Can help to highlight weakness with heating, such
as poor connection due to rough surfaces or
broken strands on cables
Improved inductive load performance
n n nn n n
Auto start
n n nn n n
Inadvertent connection to live line supply or
n n nn n n
Testing just continues as normal
Noise immunity specified at Make measurement in harsh environments
n n nn n n
n n nn n n
User interchangeable detachable Continuous testing with optional second battery.
n nn n
manoeuvrability
Continuous testing from mains ideal for
manufacturing applications
Always ready to test no waiting for battery to
charge
Can be transported in any wet conditions
Can be operated in the rain
Built to take the knocks in the most arduous of
conditions
Test result storage with memos Ideal for predictive maintenance systems
Feature DLRO10 DLRO10HD DLR010X Benefit/s
temperature compensation
Can help to highlight contamination
Extends battery life
High power output Can help to highlight weakness with heating, such
as poor connection due to rough surfaces or
broken strands on cables
Improved inductive load performance
Fast operation without pressing test button
Inadvertent connection to live line supply or
UPS voltage will not even blow a fuse
Testing just continues as normal
Noise immunity specified at Make measurement in harsh environments
User interchangeable detachable Continuous testing with optional second battery.
Use one battery while second charges
manoeuvrability
Continuous testing from mains ideal for
manufacturing applications
Always ready to test no waiting for battery to
charge
Can be transported in any wet conditions
Can be operated in the rain
Built to take the knocks in the most arduous of
conditions
Test result storage with memos Ideal for predictive maintenance systems
Less errors in writing down test results
Save results to your PC or send to a printer
Aids rapid testing to specified limits
DLRO PRODUCT COMPARISON GUIDE
DLRO10HD
10 A Digital Low Resistance Ohmmeter
ORDERING INFORMATION
Item (Qty) Cat. No.
DLRO10HD Low Resistance Ohmmeter 1000-348
Included Accessories
DH4 duplex handspike 1.2m 6111-503
Test lead pouch (lid mounted) 1000-036
DLRO10HD user guide CD 2000-869
Warranty book 6170-618
Optional Accessories at extra cost
Calibration Shunt,10 Ω, current rating 1 mA 249000
Calibration Shunt, 1 Ω, current rating 10 mA 249001
Calibration Shunt, 100 mΩ current rating 1 A 249002
Calibration Shunt, 10 mΩ current rating 10 A 249003
Certificate of Calibration for Shunts, NIST CERT-NIST
Replacement tips for DH4, DH5 and DH7 handspikes
Needle point 25940-012
Serrated end 25940-014
Optional Test Leads at extra cost
Duplex Leads
DH5 straight duplex handspikes (2)
One has indicator lights 2.5m/8ft 6111-517
DH7 Duplex handspikes (2) suitable
for working on 600 V. systems 2.5m/8ft 1001-035
Duplex Handspikes (2) with spring
loaded helical contacts 2m/7ft 242011-7
DH1 2.5m/8ft 6111-022
5.5m/18ft 242011-18
only 1 lead supplied DH2 6m/20ft 6111-023
9m/30ft 242011-30
DH3 9m/30ft 6111-024
Item (Qty) Cat. No.
Straight Duplex Handspikes (2)
Heavy Duty with fixed contacts 2m/7ft 242002-7
5.5m/18ft 242002-18
9m/30ft 242002-30
Duplex Heavy Duty 5cm (2”)
C-Clamps (2) 2m/7ft 242004-7
5.5m/18ft 242004-18
9m/30ft 242004-30
Duplex handspikes with replaceable
Needle Points 2m/7ft 242003-7
Duplex 1.27 cm (1/2“)
Kelvin Clips, (2) gold plated 2m/7ft 241005-7
silver plated 2m/7ft 242005-7
Duplex 3.8 cm (1 1/2”)
Kelvin Clips (2) 2m/7ft 242006-7
5.5m/18ft 242006-18
9m/30ft 242006-30
Single Leads
Single handspike (1) for potential
measurement 2m/7ft 242021-7
5.5m/18ft 242021-18
9m/30ft 242021-30
Current clip (1) for current
connections 2m/7ft 242041-7
5.5m/18ft 242041-18
9m/30ft 242041-30
Note: For more details of optional lead sets see separate test
lead datasheet DLRO_TL_DS_en_V04.pdf
UK
Archcliffe Road Dover
CT17 9EN England
T +44 (0) 1304 502101
F +44 (0) 1304 207342
UNITED STATES
4271 Bronze Way
Dallas TX 75237-1088 USA
T 800 723 2861 (USA only)
T +1 214 333 3201
F +1 214 331 7399
OTHER TECHNICAL SALES OFFICES
Norristown USA, Sydney AUSTRALIA,
Toronto CANADA, Trappes FRANCE,
Kingdom of BAHRAIN, Mumbai INDIA,
Johannesburg SOUTH AFRICA and
Conjure THAILAND.
Registered to ISO 9001:2000 Cert. no. Q 09290
Registered to ISO 14001-1996 Cert. no. EMS 61597
DLR10HD_DS_en_USV03
www.megger.com
Megger is a registered trademark
